Typewriter



Dec. 18, 1928.

O. A. HOKANSON TYPEWRITER Filed March 17, 1924 3 Sheets-Shet 0 I @uvrzior fa MW x5] V X Dec. 18, 1928. 1,695,492

0. A. HOKANSON TYPEWRITER Filed March 17, 1924 5 Sheets-Sheet 2 Jiizfenzor Dec. 18, 1928.

O. A. HOKANSON TYPEWRITER Filed March 17, 1924 5 Sheets-Sheet mam Patented Dec. 1 1928.

UNITED STATES 1,695,492 PATENT OFFICE.

omo noxnnsou, or woonsroox, ILLINoIsnss eNoR T woons'rocx mm. WRITER COMPANY, on woonsrocx, ILLINOIS, A CORPORATION on ILLINOIS.

Application filed March 17, 1924. Serial No. 699,727.

This invention relates to typewriting machines, and more especially to machines of this nature provided with a power driving device.

The invention has for its object the provision of a typewriting machine which shall be controlled by a keyboard in the usual manner, but in which the work of moving keys and other parts shall be performed by power actuated mechanism.

Another object of the invention is to provide a power actuated typewriter which shall be of improved construction and operation.

The invention is exemplified in the cornbination and arrangement of parts shown in the accompanying drawings and described in the following specification, and as more particularly pointed out in the appended claims.

In the drawings- Fig. 1 is a fragmentary vertical sectional view of a typewriting machine showing one embodiment of the present invention;

Fig. 2 is a view similar to Fig. 1, but.

showing mounting for the platen;

Fig. 3 is a fragmentary bottom plan view with parts in section showing the mechanism illustrated in Fig. 2;

Fig. 4 is a fragmentary top plan view with parts in section showing the motor and its associated parts;

Fig. 5 is a fragmentary front elevation of the adjusting lever for the platen; and

on line 6-6 of Fig. 2.

It is well known that prolonged operation of a typewriting machine produces a fatiguing strain on the operator because of the force with which the keys must be struck in order to produce the proper impression from the type. This is especially true of machines having a formof action in which the type members make their impression at about the time at which they reach the limit of a prescribed range of movement, and especially in machines of this type provided with moving parts having considerable weight to impart the necessary momentum to produce a clear impression at the extremities of the movements of the type carrying members. v In the present invention this difficulty is avoided and a more speedy action is obtained by providing power mechanism for producing the movement of the operating parts, it being necessary to depress the keys only a suflicient amount to control the power mechanism.

Referring more particularly to the drawing, the numeral 10 designates the frame of a typewriting machine having a plurality of horizontally sliding type carrying members 11 which travel in guides in the upper plate 12 of the frame, the guides all converging toward a common center adjacent the front face of the platen 13. The type carrying members 11 are moved by a pair of toggle links Hand 15 which are pivoted to one another at 16, one of the links being pivoted to the member 11 at 17, while the other link is mounted on a stationary pivot 18 on the arm 19. The arm 19 is secured to the portion 20 of the main frame by means of an integral bar 21 held by screws 22 and 23.. The arm 19 is bifurcated, the forward portion supporting a pivot 24 having a cam 25 journaled thereon; The rear portion of the arm 19 carries a pivot 26 on which a bell-crank 27 is supported. The upper arm 28 of the bell-crank 27 is pivoted at 29 to a link 30 which in turn is pivoted at 31-to a forwardly projecting bar 32 on the toggle link 15. The link 30 is extended rearwardly and provided with a weighted end 33 to impart momentum to the moving parts when the machine is operated. The lower 1 arm 34 of the bell-crank 27 underlies the 0 cam face of the cam 25. A tail piece 35 is Fig. 6 is a vertical section substantiallysecured to the bell-crank 27 in position to strike a rubber cushion 36 at the limit .of the movement of the operating parts.

' A spring 37 normally rests upon the arm 34 and holds the operating parts in their retracted position in which the weighted portion of thelink 15 rests upon a cushion 38. The arm 34 is provided with a down- 'wardly extending tappet 39 which engages a universal bar 40. A link 41 is pivotally connected at 42 to the cam 25.and has its lower end pivoted at 43 to a pivoted member .44 mounted on the rod 45 extending transversely of the machine. An actuator 46 is pivotally connected at 47to the member 44 and is provided at its rear end with a hook 48 for engaging a ratchet cylinder 49. The 106 cylinder 49 has its opposite ends journaled in the side of the machine and is rovided at one end, as shown in Fig. 4, with gears 50 connecting the cylinder to a motor 51 by means of shaft 52 and worm gear 53. The

.in a well motor 51 is mounted, in the embodiment shown, at the rear of the frame 10. A spring 54 normally holds the actuator 46 out of engagement with the .ratchet cylinder 49, the upward movement of the actuator being limited by a bar 55 extending transversely of the machine in position to engage. the various actuators 46. The rear end of the actuator'46 is extended to provide a cam face 57 for engaging a roller 58 extending transversely of the machine and supported by a pair of arms 59 One at each side of the machine pivoted at 60 to the frame. Each of the arms 59 has a jaw member 61 which engages an eccentric cam 62 on a shaft 63 journaled in the side frames of the machine.

The shaft 63 as shown in Fig. 4 is provided with a hand lever 64 which carries a sprin pressed finger piece 65 having a pin remova ly engaging openings in a quadrant 66 to retain the shaft in various positions of adjustment. It will be apparent that as the shaft 63 is rotated the arms 59 and consequently the roller 58 will be adjusted toward or away from the projections 57 of the actuator 46.

Each of the actuators 46 is provided with a laterally extending lug 67 which engages a book 68 formed on the upper end of a connector 69 pivoted at 70 on the key lever 71. The key levers 71 are pivoted at 72 near the rear of the machine and are held in their uppermost positions by springs 73 nown manner.

Each of the connectors 69 is provided with a slot 74 to provide limited vertical movement relative to the key lever 71 and a stop'75 engages a projection 76 on the key lever to limit the forward pivotal movement of the connector.

Any suitable switching mechanism may be used for starting and storming the motor 51, and when the motor is operating; the ratchet cylinder 49 will continuously rotate in a clockwise direction as viewed in Fig. 1.

If now any. one of the key levers 71 is depressed the hook 48 will engage one of the teeth of the ratchet cylinder so that the actuator will be movedrearwardly for a short distance. The movement of the actuator in its depressed position will free the contact member 67 and 68 so that the actuator will be free to return to its uppermost position under the influence of spring 54. The cam face 57 acting on the roller 58 will positively disengage the hook 48 ffom the tooth of the ratchet drive cylinder 49 so that the actuator will be positively freed at a definite time. the ea act time of release being determined by the adjustment of the roller 58 by the cam 62. The impulse thus given to the actuator 46 will be transmitted to the cam 25 through the link 41 and from the cam 25 to the bell-crank 27 and link 30 to the toggle arms 14 and 15 and to the type support 11. This will start the type support in its sliding movement toward the platen 13, but before it reaches the limit of its movement as determined by the toggle links 14 and 15 and the stop 36 the actuator will -be-'released from the power drive sothat the stroke will be completed by the momentum-of the parts including the weighted member 33. I 7

It will be seen that the power drive is es 'pecially adapted toa type bar action. of

this kind because of the fact that greater momentum can be imparted to the moving parts during a short range of movement than can be done by manual op'era-tion. If the operator should. hold the key lever 71 depressed for a suflicient length of time to permit the actuator 46 to return to normal position prior to the release of the key everthe pivoted hook portion 68, together with the lower bevelled edge of the projection 67 will cause the connector 69. to snap into place above the projection 67 whenever the key lever 71 is released.

Because of the radial position of the type bar supports 11 the position of the pivots 24 may vary fore and aft of the machine. It will be desirable to locate the transverse bar 25 about midway between the extreme fore and aft positions of the pivots 42 so that the angularity of. the link 41 will not .vary too greatly. The position of the pivots 43 on the arm 44 may be varied to compensate for any variation of the type bar action due to the angularity of the links 41. It will be understood that the actuators 46 are arranged in arallel relation so that they travel at rigl it angles to the cylinder 49. This will bring the pivots 42 and 43 slightly out of parallel relation for the-type actions at the sides of the machine, but this lack of parallelism may be compensated for by imv parting a slight twist to the links 41.

It will be understood that the adjustment of. the roller 58 will changethe period of contact between hook 48 and the teeth of the roller so as to impart varying degrees of momentum to the type action, and thus give varying force to the impression of the type upon the paper. vSince the type supports are moved to the limit of their path of travel at each operation and are not arrested by the platen, 1t is desirable to adjust the platen toward and from the impression point so as to insure the proper contact of the type upon the a-per. 11 order to secure this adjustment 0 the platen 'a slide 77 is mounted in ways formed in the top plate 12 and is provided with a rearwardly projecting bracket 78 having a plate 79 projecting laterally from each side of the bracket. Arms 80 are a'djustably mounted by means of pivoted blocks 81 and links 82 at each side of the bracket 78. These arms support atrack 83 on which the platen carriage 84 is mounted for lateral movement. The travel of the carriage is controlled by a rack 85 and an 'escapement pinion 86 operated in any well known manner. A link 87 is secured to the front ofithe slide 77 and is threaded into a sleeve 88 at its for.-

ward end. The sleeve 88 is journaled to rotate in the front plate 89 and has an arm 90 adjustably secured thereto by a screw 91. A spring 92 is interposed between the rear face of the plate 89 and a collar 93 fixed to the link 87.-

Rotation of the arm 90 draws the link 87 forwardly by means of its threaded connection with the front end of the. link. Movement of the arm in the opposite direction releases the link 87 so that it is moved rearwardly by the spring 92. By this means the platen 13 may be accurately adjusted toward and away from the contact 'point with the type. A graduated segment 94 may be provided for indicating the position of the arm 90.

I claim:

1. The combination with a sliding type carrier, of a vertically movable member for actuating said type carrier, a power drive, a horizontally movable actuator arranged to engage said power drive, a pivoted member connected with said actuator, and a link consliding type carrier, a toggle for imparting movement to said type carrier and for arresting said type carrier at the limit of it's range :of movement, a platen adjustable toward and away from said type carrier, op: erative mechanism for said toggle,cushioning means for arresting said operative mechanism at the limits of the movement thereof in either direction, a spring for retracting said type carrier, a motor actuated drive, an actuator arranged to engage said drive, means for operatively connecting said actuator with said toggle operating mechanism, a key lever, a connector arranged to engage said actuator to move said actuator into operative relation with said drive and disengageably therefrom by the movement, imparted to said actuator by said drive, and an adjustable device for disconnecting. said actuator from said drive during the movementimparted by said actuator to said type carrier. 1

In testimony whereof I have signed my name to this specification 011 this 15th day of March, A. D. 1924.

@TTU A. HOKANSON. 

